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Attura AI · Anomaly Detection

Thousands of HR records. One that does not follow the pattern.

Attura AI uses Isolation Forest — a label-free anomaly detection method — to flag attendance, overtime, leave, and payroll patterns that deviate from your organization's norms.

The AI points. HR decides.

Coming Soon · In development

The data grows every day. Reviewing it row by row does not.

Your HRIS records attendance, overtime, leave, business trips, and payroll — thousands of new rows every month.

The problem is not a lack of data. Unusual patterns can look small when seen one record at a time, and manual review only gets harder as volume grows.

Anomaly detection looks across records at once, then hands the result to a human.

What is an anomaly?

An anomaly is simply an observation that does not follow the pattern of the others.

A 13:47 clock-in among a row of 08:00s does not mean a violation. It is a signal to review — maybe the shift changed, maybe a half-day permission, maybe it does need checking. The decision stays with HR.

How it works

The unusual isolates faster.

Isolation Forest does not look for "what is wrong". It draws separating lines at random positions, then counts: how many lines does it take before an observation stands alone?

  1. 1

    Start with every observation

    Each point is one observation from HRIS data — for example, an employee's overtime pattern in one period.

  2. 2

    The model draws a random line

    A feature is picked at random, then a split value is picked at random between its smallest and largest values. The space splits in two.

  3. 3

    Line after line

    The splitting repeats. Points that crowd together are hard to separate — they keep sharing space with their neighbours.

  4. 4

    The far-away one is quickly alone

    An unusual observation gets boxed in alone after only a few lines. That number of lines is its "path length".

  5. 5

    Hundreds of trees, one score

    The process repeats across many random trees. A short average path yields a high anomaly signal — ready for HR review.

Why "isolation"?

Point A — inside the crowd

9+ lines to separate it

It keeps sharing space with many neighbours. Its path is long — its anomaly signal is low.

Point B — far from the crowd

3 lines and it stands alone

Isolated quickly in nearly every random tree. Its path is short — its anomaly signal is high.

This intuition — yang tidak biasa lebih mudah diisolasi — adalah seluruh dasar metode ini. Tanpa label, tanpa daftar aturan, tanpa definisi "salah".

Inside your HRIS

The same model reads four data domains already in Attura. Always in the same shape: pattern → signal → HR review.

Attendance

Pattern
Most employees keep a stable rhythm of clock-in times and locations.
Signal
One attendance pattern shifts drastically from its own habit and the team's.
HR action
Open the attendance records and their context — shifts, permissions, assignments.

Overtime

Pattern
Team overtime usually moves within a historical range: 2h · 3h · 2.5h · 3h.
Signal
One period records 11h — far outside anyone's historical pattern on that team.
HR action
Review the overtime records, requests, approvals, and the work context.

Leave

Pattern
Leave behaviour follows seasonal and personal patterns.
Signal
A particular timing and frequency combination deviates from both patterns.
HR action
Review the leave records with their organizational context — projects, seasons, policies.

Payroll

Pattern
Salary components follow historical patterns and the organization's structure.
Signal
A value or combination of components differs significantly from the learned pattern.
HR action
Review the payslip, inputs, and source data before payroll runs.

An anomaly does not mean fraud, does not mean an employee is at fault, and does not mean payroll must be wrong. An anomaly is a signal to review. The numbers in the visuals above are illustrative examples.

From signal to decision

  1. Data
  2. Model
  3. Anomaly signals
  4. HR review
  5. Decision

The AI does not make HR decisions. It does not declare anyone at fault. It does not replace human judgment. It helps prioritise what deserves a look first.

What the model sees, and what HR sees

Model

Anomaly signal · overtime pattern · July period

The model does not read human stories. It reads patterns in the data it is given.

HR

  • The flagged employee and period
  • Source records: overtime, requests, approvals
  • The historical pattern for comparison
  • Context: projects, shifts, policies

The signal opens the context — the context produces the decision.

A signal, not a verdict.

  • Unusual does not mean wrong.
  • Unusual does not mean fraud or misconduct.
  • Signal quality depends on data quality.
  • Historical patterns can contain noise and bias.
  • Human context remains essential — which is why every signal stops at HR's desk, not at an automated decision.
For the technical reader: how Isolation Forest works

Isolation Forest (Liu, Ting & Zhou, IEEE ICDM 2008) is an unsupervised anomaly detection method. Each isolation tree is built by picking a feature at random, then a random split value between that feature's minimum and maximum — repeatedly, until observations are isolated.

The number of splits needed to isolate an observation equals the path length from the tree's root to its leaf. Averaged over many random trees (an ensemble), a shorter path means the observation is easier to isolate — and more likely to be an anomaly.

The resulting score is a ranking of anomaly signals, not a probability of wrongdoing. Thresholds and interpretation need to be contextualised to each organization's data.

Reference: F. T. Liu, K. M. Ting, Z.-H. Zhou, "Isolation Forest", IEEE ICDM 2008 · scikit-learn documentation: outlier detection.

Coming to the Advance plan

Attura AI is under development and will be available automatically to Advance plan subscribers once released — reading the data already in your HRIS.